1. Field of the Invention
The present invention generally relates to the field of in seat power systems and, more particularly, to a peer-to-peer control and decision making system for controlling power application to a group of seats.
2. Description of the Related Art
When used in broadcast and industrial applications, large industrial and broadcast systems permit users to reliably control the systems, and to do so in real time. The majority of such systems are based on a “Two Layer Star Controlled System”. That is, one central control computer, comprising a top layer “star” (“Master Control”), which controls local control computers. These local control computers each control smaller control logic or microprocessors, which comprise a second “star” layer.
Such a “tiered star” control system is used as a conventional means to control existing aircraft cabin power management systems. That is, the “Master Control” resides at an end of a network, and remote devices “request” permission to perform a given function from the master control. The “Master Control” subsequently “grants” the remote unit permission to proceed with the desired function, such as turning on a seat motor, a light, etc. This process is controlled in this manner because only the “Master Control” contains knowledge of the power consumption levels, which it periodically requests from the remote devices, as well as information concerning the available power. Here, the “Master Control” acts as a “traffic cop,” telling each unit when to activate/deactivate a specific function.
While such systems work very successfully when used within industrial and broadcast applications, they tend to be overly expensive, due to the need for a multitude of powerful computers for providing the necessary control logic. For example, in conventional systems, the “Master Control” must be a very powerful computer, and hence an expensive computer. An inexpensive “Master Control” computer can quickly become overloaded when receiving and responding to messages such that the system quickly grinds to a halt. This means that the “Master Control” is an expensive device, one which many airlines have been unwilling to invest in for the perceived benefits. As a result, many of the installed systems are completely “dumb” systems, providing only DC power for laptop computers, and providing none of the benefits of power management, or ease of use. In some cases, airlines using competing systems are reduced to activating and deactivating the system via circuit breakers; a failure of a single unit requires the disablement of an entire column of seats by the flight crew. Although such an arrangement is inconvenient, many airlines are currently subject to the use of such systems.
An additional disadvantage of this hierarchal, or “Master control” type architecture, is that the decision making process is controlled by the top level controller. When the such a system receives a number of simultaneous requests, slow system response times may occur. The system can also completely fail, where a single point of failure is the “Master Control. ” For example, a remote device must transmit a message for permission to perform a given function, such as turn on a motor. The “Master Control” must receive the message, decode it, and then transmit a message back to the remote device to thereby grant permission to the remote device to perform the specified function. The remote device then decodes this second message, prior to actually turning on the motor. If only a single unit at a time requests permission from the “Master Control”, then the system can respond fairly quickly, with a minimum amount of perceptible delay between the time a passenger pushes a button and the actual movement of the motor. When multiple simultaneous requests from several users to the “Master Control” are made, significant time delays in responding to the requests can quickly occur, just like a busy server on the Internet can quickly become very slow in its response times.
Primex Aerospace Company manufactures an In-Seat Power system. According to this manufacturer, this system requires a “Master Control” for the system to operate. Another manufacturer, Kid Systeme GmbH, located in Germany also manufactures an In-Seat power system that also utilizes the aforementioned “Master Control”. However, these In-Seat power systems posses the problems associated with a “Two Layer Star Controlled System.” That is, they are overly expensive to manufacture, they possess slow response times, and they cease to operate when the “master control” fails. Accordingly; it is apparent there is a need for a lower cost, and more fault tolerant system for use in a commercial aircraft In-Seat Power System.